A cell population can be made amenable to the uptake of exogenous molecules by rupturing the plasma membranes of the cells. This allows the incorporation of the desired gene molecules into targeted cells. Over- rupturing of cell membranes will lead to undesirable loss of viability of the cell populations since the ruptures produced may be beyond repair. Under-rupturing, on the other hand, may not produce an adequate degree of gene transfection. This SBIR Phase I application proposes to develop a micrograte disruption is expected for all cells in a given population when microgrates are in effect. An optimum degree of membrane rupture will maintain the viability of a cell population and achieve receptiveness to the desired exogenous molecule(s). The micrograte system concept is simple and economical, and appears to be an ideal device for gene transfection. Emphasis will be placed on the microfabrication of microgrates, the detailed configuration of the microgrates and the surface chemistry of the grating elements. Phase II of this research will focus on the evaluation of several prototypes of micrograte systems for gene therapy applications. PROPOSED COMMERCIAL APPLICATIONS: Once evaluated and optimized, the intrinsically straightforward and economical micrograte system will simplify the gen loading process while maximizing the utilization of the genes and the viability of her cell population. It is therefore expected that the use of microgrates will play an important role in lowering the costs associated with gene therapy.